Quote:
Simple. Do nothing.
If your relationship is good, by trying to pull you apart he will push her away.
You don't have to do anything
I disagree, although it depends what his preserved value is to his gf and friend (is he the the alpha male or the beta bitch?) If he is in fact the alpha he can literally tell the guy to fuck off without anyone questioning him, if however he is the weak beta in the group the guy might blow him out and he will come off as an asshole.
Here is the thing, if he's not the alpha male its time to step up and take control of the situation like an alpha, gain control of the group and of the relationship. You want to be a bitch your whole life? or step up and be the alpha male? Some guys will never understand this concept, and those are the guys who don't have it in them to be leaders.
I consider my self the "alpha" in my circle of friends and family and if something bothers me I will let it be known, if someone doesn't like it does not phase me! nor should it....I have no one to please but my self. Why would I hang around someone who don't get along with? Id rather be around people who I like.
Its not beta to tell someone who has no respect for you and is clearly trying to drive a wedge between you and your gf to fuck off....it would be beta to not do this! Think of the alpha lion in the wild, what does he do when one of the beta lions is doing something he does not like? He tel him to fuck off lion style lol and no one in the pack questions that lion because he is the leader.